A fixed skeleton that reads like a letter
The letter is five paragraphs in a fixed order: a greeting, one opening sentence, the match bullets, a closing and a signature. When you only fill the three required fields, four of those paragraphs survive (the matches paragraph stays off until you give it a line), so the shortest possible letter still reads complete - never a list of prompts, always prose.
The opening sentence is stock: it names the position and the company you typed and nothing else. No invented motivation, no copied flattery, no claim the page has no right to make on your behalf - the skeleton is generic by design, and the words that make the letter yours are the lines you write yourself.